Cationic copolymer enhances 8–17 DNAzyme and MNAzyme activities

Abstract

DNAzymes are DNA molecules capable of catalytic activity. The catalytic core of DNAzymes can be separated and conjugated with target binding arms to create allosteric DNAzymes known as multi-component nucleic acid enzymes (MNAzymes). Two widely used DNAzymes are the 10–23 and the 8–17 DNAzymes. These DNAzymes differ in catalytic core structures, cleavage sites, and reactive metal ion cofactors. Previously we showed that the presence of a cationic comb-type polymer poly(L-lysine)-graft-dextran (PLL-g-Dex) improved activities of the 10–23 DNAzyme and MNAzyme by facilitating assembly of the catalytic complex. In this work, we demonstrate that PLL-g-Dex enhances activities of the 8–17 DNAzyme and MNAzyme; poly(allylamine)-graft-dextran and cationic homopolymers did not enhance activities. Metal ion and pH dependences were observed in the presence of PLL-g-Dex, suggesting that the cationic copolymer did not impede the interaction between the metal ion and the DNA-based enzymes. Thus, PLL-g-Dex has chaperone-like activity for DNAzymes and MNAzymes regardless of structures, cleavage sites, and cofactors.